'River' in the Bible

And I said to the king, If it please the king, let letters be given me to the governors beyond the river, that they may set me forward till I come into Judah;

And I came to the governors beyond the river, and gave them the king's letters. Now the king had sent captains of a force and horsemen with me.

And next to them repaired Melatiah the Gibeonite, and Jadon the Meronothite, the men of Gibeon and of Mizpah, to the seat of the governor on this side the river.